Converting 1080P directly to an iPod-ready format
The goal was to convert some 1080P video from my Canon 5D directly into an iPod readable format. However, as I was overly tired on this day, my mind defeated me. Essentially what happened was that after I rendered out the video and loaded it to the iPod, I kept seeing only three quarters of the video. Flummoxed, I thought it must be a rendering problem. Long story short, I found that the problem was not with my rendering parameters, but the fact that my iTouch has a zoom/scaling feature that I forgot about, but had enabled. Here is the little bugger:
So I had spent about three hours until 2am fighting with encoding parameters, re-encoding video, transferring many test files to my Mac and then loading them to the iPod, only to find that the source of the problem was this little stupid icon on the iTouch.
Boy, am I dense.
A Learning Experience
I did learn a few things through my travails this weekend:
1) The el cheapo haze filter on my camera shows a lot of lens flare and needs to be replaced.
2) Don't merge a longer audio stream with a shorter video stream or else you'll be wondering why your 1m45s video is suddenly 9m30s. Duh.
3) When encoding videos to H264 format, always try to use resolutions where the height and width are divisible by 16. This will make the level of compression and quality of the resulting video better. I will post separately about resolutions that are divisible by 16.
4) A dvd video encoded by ffmpeg using -target ntsc-dvd and then downrezzed using the following command syntax will NOT have the proper aspect ratio once loaded onto the iPod:
ffmpeg -y -i ${NAME}.mpg -an -v 1 -threads 8 -vcodec h264 -b 250k -bt 175k -refs 1 -loop 1 -deblockalpha 0 -deblockbeta 0 -parti4x4 1 -partp8x8 1 -me full -subq 1 -me_range 21 -chroma 1 -slice 2 -bf 0 -level 30 -g 300 -keyint_min 30 -sc_threshold 40 -rc_eq 'blurCplx^(1-qComp)' -qcomp 0.7 -qmax 51 -qdiff 4 -i_qfactor 0.71428572 -maxrate 450k -bufsize 2M -cmp 1 -s 720x480 -f mp4 -pass 1 /dev/null
ffmpeg -y -i ${NAME}.mpg -v 1 -threads 8 -vcodec h264 -b 250k -bt 175k -refs 1 -loop 1 -deblockalpha 0 -deblockbeta 0 -parti4x4 1 -partp8x8 1 -me full -subq 6 -me_range 21 -chroma 1 -slice 2 -bf 0 -level 30 -g 300 -keyint_min 30 -sc_threshold 40 -rc_eq 'blurCplx^(1-qComp)' -qcomp 0.7 -qmax 51 -qdiff 4 -i_qfactor 0.71428572 -maxrate 450k -bufsize 2M -cmp 1 -s 720x480 -acodec aac -ab 160k -ar 48000 -ac 2 -f mp4 -pass 2 -threads 8 ${NAME}.mp4
So don't try that at home, kids.
I had previously been using this string of encoding parameters to encode a video of my band rehearsals. The encode was from a DVD source file, so perhaps I will just use the 1080P as source going forward. I will have to test this out first. Strangely, the conversion of the audio from AC3 format had audible hiccups from time to time. Since this process was working fine on Fedora 7, perhaps this is just an issue with Fedora 10.
Downrezzed 1080P Video Ready for the iPod
The following two pass Cinelerra encoding parameters via yuv4mpeg stream worked well to produce a high quality video from 1080P source. In short, you will do two renders from a YUV4MPEG stream:
render 1: the pipe to /dev/null in order to create the optimization log
render 2: the pipe to create the file
#CINELERRA YUV4MPEG RENDER 1
ffmpeg -f yuv4mpegpipe -y -i - -an -v 1 -threads 8 -vcodec libx264 -b 1000k -bt 775k -refs 1 -loop 1 -deblockalpha 0 -deblockbeta 0 -parti4x4 1 -partp8x8 1 -me full -subq 1 -me_range 21 -chroma 1 -slice 2 -bf 0 -level 30 -g 300 -keyint_min 30 -sc_threshold 40 -rc_eq 'blurCplx^(1-qComp)' -qcomp 0.7 -qmax 51 -qdiff 4 -i_qfactor 0.71428572 -maxrate 1000k -bufsize 2M -cmp 1 -s 512x288 -f mp4 -pass 1 /dev/null
#CINELERRA YUV4MPEG RENDER 2
ffmpeg -f yuv4mpegpipe -y -i - -i /mnt/videos/projects/2009_01_23/nightUrbanIndustrialIpod.mp3 -v 1 -threads 8 -vcodec libx264 -b 1000k -bt 775k -refs 1 -loop 1 -deblockalpha 0 -deblockbeta 0 -parti4x4 1 -partp8x8 1 -me full -subq 6 -me_range 21 -chroma 1 -slice 2 -bf 0 -level 30 -g 300 -keyint_min 30 -sc_threshold 40 -rc_eq 'blurCplx^(1-qComp)' -qcomp 0.7 -qmax 51 -qdiff 4 -i_qfactor 0.71428572 -maxrate 1000k -bufsize 2M -cmp 1 -s 512x288 -acodec libfaac -ab 160k -ar 48000 -ac 2 -f mp4 -pass 2 -threads 8 %
I chose a resolution of 512x288 because:
1) the aspect ratio is the same as my 1080P source video, 16:9 (1.777)
2) both the height and width are divisible by 16
3) there were no errors and it comes out looking great on the iPod
Rendering Parameters for a High Quality Vimeo Upload
Finally, I was able to output an H264 video at 1920x1080 that looks great in Vimeo. Psych! I was able to remove the ugly bottom bar seen in Vimeo from my previous post. Here is the two-pass encoding method that I used from Cinelerra. Two notes:
1) the two passes are YUV4MPEG stream renders from Cinelerra using FFMPEG and will need to be run as individual renders in Cinelerra.
2) the second pass muxes (combines) a pre-rendered audio stream with the video stream. So you'll need to render that audio file first.
Here is your first render command string (the first pass of the two-pass) that will create the optimization log:
#CINELERRA RENDER PASS1
ffmpeg -f yuv4mpegpipe -y -i - -an -v 1 -threads 8 -vcodec libx264 -aspect 1.7777 -b 9000k -bt 7775k -refs 1 -loop 1 -deblockalpha 0 -deblockbeta 0 -parti4x4 1 -partp8x8 1 -me full -subq 1 -me_range 21 -chroma 1 -slice 2 -bf 0 -level 30 -g 300 -keyint_min 30 -sc_threshold 40 -rc_eq 'blurCplx^(1-qComp)' -qcomp 0.7 -qmax 51 -qdiff 4 -i_qfactor 0.71428572 -maxrate 10000k -bufsize 2M -cmp 1 -f mp4 -pass 1 /dev/null
Here is the second render command that takes advantage of the optimization log created in the first-pass render. I rendered an audio file of my project earlier, so this second command also combines that audio file with the video for my final result:
#CINELERRA RENDER PASS2
ffmpeg -f yuv4mpegpipe -y -i - -i /mnt/videos/projects/blog/waterSmall.mp3 -v 1 -threads 8 -vcodec libx264 -aspect 1.7777 -b 9000k -bt 7775k -refs 1 -loop 1 -deblockalpha 0 -deblockbeta 0 -parti4x4 1 -partp8x8 1 -me full -subq 1 -me_range 21 -chroma 1 -slice 2 -bf 0 -level 30 -g 300 -keyint_min 30 -sc_threshold 40 -rc_eq 'blurCplx^(1-qComp)' -qcomp 0.7 -qmax 51 -qdiff 4 -i_qfactor 0.71428572 -maxrate 10000k -bufsize 2M -acodec libfaac -ab 160k -ar 48000 -ac 2 -cmp 1 -f mp4 -pass 2 %
I think the quality is bloody AWESOME! Take a gander:
2009/01/23: night, urban, industrial from crazed mule on Vimeo.
Conclusion
Through pain, there can sometimes be the brighter side. In this case, I learned a few things. In retrospect, I may have chosen my production company's name correctly. A mule is one stubborn beast.
Related to crazed mules, here is a story I stumbled upon the other day you might find funny:
The Day the Mules Went Crazy
The Mule
Reference
H264 Encoding
FFMPEG HowTo
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